Building interior windows insulation panels

[Nightjar]

It is well worth it.

Colin Bignell

[SteveW]

As a worker stuck in an office (well various offices over the years as I work 3 to 18 month contracts) I've found virtually all vastly overheated. The one I'm in now has the thermostats set to 23°C with notices on saying not to touch them. Many people are complaining of the heat, opening windows (only a few per floor can be opened though) and just generally falling asleep. How much energy could be saved by turning them down to a more comfortable 20 to 21°C?

SteveW

[stuart noble]

Probably bone dry too. Great environment for the spread of all things airborne

[John Rumm]

Compare with the "before" picture here:

[John Rumm]

Some sort of tambour style integrated roll down shutter might work well, so you can pull it down when required, but normally its hidden in the top of the window reveal.

[John Rumm]

SiL's place still has those - very tall sliding sash windows (probably about 8 - 10') with shutters built into the window reveals at a slight angle. Either bi or tri fold. They just look like part of the wide architrave / decorative trim.

[John Rumm]

Conventional (as in older) don't need it since they leak air like a sieve anyway.

If you build totally air tight (as is the modern trend) then some form of ventilation becomes ever more important to clear stale air and prevent internal condensation.

[John Rumm]

I find a noticeable difference here on windy days... I was toying with modifying the external temperature sensor for my weather compensator to include some notion of wind speed.

[harryagain]

Most domestic temperature conrols are pretty micky mouse. You can buy energy management controls with this feature also solar gain etc etc. The wind sensor was a thermisor, cooled if there was any wind. Some have a self learning predictive feature.

Commercial devices have had all this stuff fors years, most had to be manually set, PITA in days of yore. I think some domestic stuff has it now with the cost of energy.

[Chris J Dixon]

Additionally, many shops have a policy of leaving their doors open all year, to encourage us to enter. Simply wasted energy.

Chris

[Nightjar]

An open doorway with a properly designed and installed air curtain (not all are) can be more effective at keeping warmth in than a door without that is frequently being opened and closed. Automatic doors with an air curtain offer the best solution though.

Colin Bignell

[Nightjar]

Interesting article. However, if I had the same aims as Harry, I wouldn't have chosen a bungalow. For the same volume, a detached house will have less surface area than a detached bungalow.

However the figures in the article are slightly suspect. Elsewhere, Harry stated that he has 4kWp of panels installed. In the article, he claims that those have produced 4000 kwh each year for 4 years. The Centre for Alternative Technology calculator suggests that, in Herefordshire, 4kWp installed should give an output of around 3,400 kWh pa. However, they also state that a 5% drop in output during the first

12 months is not uncommon for modern solar PV panels.

At least it answers one question he was remarkably coy about in another forum. His installed capacity is not more than 20% above his use, so he is not defrauding HMRC by accepting the tax relief on the payments.

Colin Bignell

[Tim Watts]

On Monday 11 November 2013 07:54 Chris J Dixon wrote in uk.d-i-y:

And isn't it interesting that the gov want to stop YOU using 100W incandescant lamps, but does nothing about such glaring waste?

[Huge]

And 1200W vacuum cleaners ...

And much other similar waste.

[John Rumm]

That's because YOU does not have an organised system of lobbying for things that would be of benefit to you...

[John Rumm]

Solar gain is less of an issue since the internal room stat / TRVs etc will compensate for that without too much difficulty.

The Vaillant external sensor is basically a thermistor in a small box... but since it has no compensating heater, its not particularly sensitive to wind chill. It gives a fairly accurate "dry bulb" temperature though. Ideally one would have a separate wind speed input to the control system to shift to a more aggressive compensation curve, however "faking" it by creating the impression the temperature has dropped when you get wind speeds over a certain threshold would also work (even if that would make the external temperature read out on the room stat "lie")

I would not have thought there is much additional energy efficiency to be gained - its more of a comfort issue. Once you have a compensation cure selected that matches the building the system does a remarkably good job of creating a very even and consistent temperature. The only thing that interferes with that is high wind - but compensating would use more fuel rather than less.

[harryagain]

My shutters are fitted with "lift off" hinges. Not that I can be bothered taking them off.

[harryagain]

All external control sensors are about prediction. It takes time for external weather effects to filter through the structure. If you can predict them, there is scope for saving energy. Eg, turn the heating off early/turn down if it warms up outside and vice versa.

The technology reckons to be good for a 10% saving on the energy bill. Could be Kmany in large buildings. But it has to work right. Some have an adjustable setting for building insulation and/or some for thermal mass. Some reckon to be "self learning".

Many work on/adust zone control valves.

But you need the pukka controls and sensors.

[polygonum]

Today's bad experience was of working sat on a stool where I had to lean over a convector heater to reach the keyboard! I'd guess that was 2 kW going past my head, neck, arms...

Can't help thinking that perhaps shops and offices should be forced to disclose their fuel bills. Seeing that some shop is paying vast sums for unnecessary heating might suggest their prices and in consequence also rather high.

[John Rumm]

The significance of the effect will depend on the time constant of the building (which itself may not even be constant).

Unless you have a building that really takes days to reach temperature, you will get the lions share of any additional savings with basic weather compensation.

(assuming you are starting with a modern HE heating system of course)

I would be surprised if you could get that much additional saving over a weather compensated condensing boiler system in the average home. You would also run into the usual problem that befell all of dribbles hugely complex grand schemes; the addition capital cost far outweighed the savings over the life of the system.

Yup adaptive control is relatively easily doable - but it does require that the usage pattern be fairly similar day to day.

In this day and age, you could probably roll your own with a rPi and pile of TWI sensors. ;-)